  html {
   /* 盒子大小包括边界 */
    box-sizing: border-box; 
  }
  *, *:before, *:after {
    box-sizing: inherit;
    user-select: none;
  }
  
  body {
    background-color: #aaa;
    font-family: Sans-Serif;
  }
  
  canvas {
    background-color: #fff;
    border: 1px solid black;
    width: 1000px;
    height: 800px;
    display: block;
  }

  #uiContainer {
    position: absolute;
    top: 10px;
    right: 10px;
    z-index: 3;
    font-family: monospace;
    pointer-events: none;
  
    text-shadow:
     -1px -1px 0 #FFF,
      1px -1px 0 #FFF,
      -1px 1px 0 #FFF,
       1px 1px 0 #FFF;
  }
  #ui {
    opacity: 0.8;
  }
  #ui>div {
    pointer-events: none;
  }
  #ui input, #ui select, #ui option, #ui canvas {
    pointer-events: auto;
  }
  
  .gman-slider-label, .gman-widget-label, .gman-checkbox-label {
    font-size: small;
    min-width: 10em;
    text-align: right;
  }
  .gman-checkbox-label {
    pointer-events: auto;
  }
  .gman-widget-value {
    float: right;
    font-size: small;
    order: 1;
    min-width: 3em;
  }
  
  .gman-slider-upper {
    height: 1.5em;
  }
  .gman-slider-outer, .gman-widget-outer {
    float: right;
    display: flex;
    align-items: center;
    height: 1.7em;
  }
  .gman-widget-slider, .gman-widget-checkbox, .gman-widget-select {
    opacity: 0.5;
    font-size: large;
    margin-left: .3em;
    margin-right: .3em;
  }
  .gman-widget-select {
    font-size: small;
  }
  .gman-widget-slider {
    min-width: 120px;
  }
  